Portrait after a Costume Ball (Portrait of Madame Dietz-Monnin)

This unusual 1877 work from the Art Institute of Chicago depicts a masked woman at a costume ball — probably Madame Dietz-Monnin, a Parisian socialite — shown from a deliberately disorienting angle, with a male companion cropped at the picture's edge. Degas was fascinated by the ambiguity of the masked ball: identity concealed, social performance made explicit. The composition, with the woman pushed to the right and the space around her left open, is one of his most radically cropped and asymmetrical. This painting sits at the intersection of his interest in portraiture, theatre, and the observation of social ritual in modern Paris.

Degas works in oil with a deliberately loose finish in the background, contrasting with the precisely rendered mask, pearls, and fan. The foreshortened figure of the male companion at left — showing only a fragment — demonstrates his boldest cropping technique. The palette balances warm skin tones against the cool white and silver of the costume.